private void appendCharacter(Document doc, Element parent, BxChunk chunk, Object... hints) {
   Element node = doc.createElement("Character");
   appendPropertyIfNotNull(doc, node, "CharacterID", chunk.getId());
   appendBounds(doc, node, "CharacterCorners", chunk.getBounds(), hints);
   appendPropertyIfNotNull(doc, node, "CharacterNext", chunk.getNextId());
   appendProperty(doc, node, "GT_Text", chunk.toText());
   parent.appendChild(node);
 }